plugin/src/main/java/lol/pyr/znpcsplus/ZNpcsPlus.java

@@ -335,7 +335,8 @@ public class ZNpcsPlus {
                         .addSubcommand("set", new HoloSetCommand(npcRegistry))
                         .addSubcommand("setitem", new HoloSetItemCommand(npcRegistry))
                         .addSubcommand("offset", new HoloOffsetCommand(npcRegistry))
-                        .addSubcommand("refreshdelay", new HoloRefreshDelayCommand(npcRegistry)))
+                        .addSubcommand("refreshdelay", new HoloRefreshDelayCommand(npcRegistry))
+                        .addSubcommand("removeduplicate", new HoloRemoveDuplicateCommand(npcRegistry)))
                 .addSubcommand("action", new MultiCommand(bootstrap.loadHelpMessage("action"))
                         .addSubcommand("add", new ActionAddCommand(npcRegistry, actionRegistry))
                         .addSubcommand("clear", new ActionClearCommand(npcRegistry))

plugin/src/main/java/lol/pyr/znpcsplus/commands/hologram/HoloRemoveDuplicateCommand.java

@@ -0,0 +1,58 @@
+package lol.pyr.znpcsplus.commands.hologram;
+
+import lol.pyr.director.adventure.command.CommandContext;
+import lol.pyr.director.adventure.command.CommandHandler;
+import lol.pyr.director.common.command.CommandExecutionException;
+import lol.pyr.znpcsplus.hologram.HologramImpl;
+import lol.pyr.znpcsplus.hologram.HologramLine;
+import lol.pyr.znpcsplus.hologram.HologramText;
+import lol.pyr.znpcsplus.npc.NpcEntryImpl;
+import lol.pyr.znpcsplus.npc.NpcRegistryImpl;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.List;
+
+public class HoloRemoveDuplicateCommand implements CommandHandler {
+    private final NpcRegistryImpl registry;
+
+    public HoloRemoveDuplicateCommand(NpcRegistryImpl registry) {
+        this.registry = registry;
+    }
+
+    @Override
+    public void run(CommandContext context) throws CommandExecutionException {
+        context.setUsage(context.getLabel() + " holo removeduplicates <id>");
+        HologramImpl hologram = context.parse(NpcEntryImpl.class).getNpc().getHologram();
+        List<HologramLine<?>> lines = new ArrayList<>(hologram.getLines());
+        List<HologramText> textLines = new ArrayList<>();
+
+        Iterator<HologramLine<?>> iterator = lines.iterator();
+        while (iterator.hasNext()) {
+            HologramLine<?> line = iterator.next();
+            if (line instanceof HologramText textLine
+                    && !textLine.getValue().equals(Component.empty())
+                    && textLines.contains(textLine)) {
+                iterator.remove();
+                continue;
+            }
+
+            if (line instanceof HologramText textLine) {
+                textLines.add(textLine);
+            }
+        }
+
+        hologram.clearLines();
+        hologram.addLines(lines);
+        context.send(Component.text("NPC lines fixed!", NamedTextColor.GREEN));
+    }
+
+    @Override
+    public List<String> suggest(CommandContext context) throws CommandExecutionException {
+        if (context.argSize() == 1) return context.suggestCollection(registry.getModifiableIds());
+        return Collections.emptyList();
+    }
+}

plugin/src/main/java/lol/pyr/znpcsplus/hologram/HologramImpl.java

@@ -101,6 +101,12 @@ public class HologramImpl extends Viewable implements Hologram {
         lines.clear();
     }
 
+    public void addLines(List<HologramLine<?>> lines) {
+        this.lines.addAll(lines);
+        relocateLines();
+        for (Player viewer : getViewers()) for (HologramLine<?> line : lines) line.show(viewer);
+    }
+
     public void insertTextLineComponent(int index, Component line) {
         HologramText newLine = new HologramText(this, propertyRegistry, packetFactory, null, line);
         lines.add(index, newLine);

plugin/src/main/java/lol/pyr/znpcsplus/hologram/HologramText.java

@@ -39,4 +39,12 @@ public class HologramText extends HologramLine<Component> {
     public boolean hasProperty(EntityProperty<?> key) {
         return key.getName().equalsIgnoreCase("name") || key.getName().equalsIgnoreCase("invisible");
     }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) return true;
+        if (obj == null || getClass() != obj.getClass()) return false;
+        HologramText that = (HologramText) obj;
+        return getValue().equals(that.getValue());
+    }
 }